Hi,
On 2020-02-08 08:55:25 -0500, Glauber Costa wrote:
> - A connect() call is issued (and in the backend I can choose if I use
> uring or not)
> - The connection is supposed to take a while to establish.
> - I call shutdown on the file descriptor
>
> If io_uring is not used:
> - connect() starts by returning EINPROGRESS as expected, and after
> the shutdown the file descriptor is finally made ready for epoll. I
> call getsockopt(SOL_SOCKET, SO_ERROR), and see the error (104)
>
> if io_uring is used:
> - if the SQE has the IOSQE_ASYNC flag on, connect() never returns.
That should be easy enough to reproduce without seastar as it sounds
deterministic - how about modifying liburing's test/connect.c test to
behave this way?
Hm, any chance you set O_NONBLOCK on the fd, before calling the async
connect?
Wonder if io_connect()
file_flags = force_nonblock ? O_NONBLOCK : 0;
ret = __sys_connect_file(req->file, &io->connect.address,
req->connect.addr_len, file_flags);
if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
fully takes into account that __sys_connect_file
err = sock->ops->connect(sock, (struct sockaddr *)address, addrlen,
sock->file->f_flags | file_flags);
appears to leave O_NONBLOCK set on the file in place, which'd then
not block in the wq?
Greetings,
Andres Freund
